Bi-directional cylinder lock

ABSTRACT

A cylinder lock mechanism is disclosed comprising a cylinder housing with a cylindrical opening and a cylinder turnable in this opening. At the turning axis of the cylinder there are a plurality of locking discs each provided with a central opening forming the keyway of the lock mechanism. The locking discs are turnable by means of a key of the lock mechanism relative to the cylinder both in clockwise and in counter clockwise direction from a key insertion position into a cylinder-releasing position. The lock mechanism also includes a turnable reset member connected through a slip clutch to the key of the lock when the key is in operating position in the keyway. Turning of the key from its cylinder-releasing position back to its insertion and removal position causes a corresponding turning movement of the reset member which is provided with contact surfaces arranged to engage the locking discs and to return them due to the movement of the reset member to their initial position, allowing removal of the key from the lock mechanism.

Sttes Patet Unite r Mertanen Nov. 19, 1974 Bl-DIRECTIONAL CYLINDER LOCK[73] Assignee: 0y Wartsila AB, Helsinki, Finland [22] Filed: Nov. 12,1973 [21] Appl. No.: 414,940

[30] Foreign Application Priority Data Nov. 13, 1972 Finland 3162/72[52] US. Cl. 70/366, 70/372 [51] Int. Cl E05b 29/02 [58] Field of Search70/362, 365, 366, 372, 70/379 R, 379 A, 380

[56] References Cited UNITED STATES PATENTS 3,621,689 ll/l97l Koskinen70/366 3,77l,340 ll/l973 Krakstrom 70/338 Primary Examiner-Robert L.Wolfe Attorney, Agent, or Firm-Waters, Roditi, Schwartz & Nissen 57ABSTRACT A cylinder lock mechanism is disclosed comprising a cylinderhousing with a cylindrical opening and a cylinder turnable in thisopening. At the turning axis of the cylinder there are a plurality oflocking discs each provided with a central opening forming the keyway ofthe lock mechanism. The locking discs are turnable by means of a key ofthe lock mechanism relative to the cylinder both in clockwise and incounter clockwise direction from a key insertion position into acylinder-releasing position. The lock mechanism also includes a turnablereset member connected through a slip clutch to the key of the lock whenthe key is in operating position in the keyway. Turning of the key fromits cylinder-releasing position back to its insertion and removalposition causes a corresponding turning movement of the reset memberwhich is provided with contact surfaces arranged to engage the lockingdiscs and to return them due to the movement of the reset member totheir initial position, allowing removal of the key from the lockmechanism.

9 Claims, 7 Drawing Figures PATENTEL M1 3.848.442

SHEET 10F '4v BI-DIRECTIONAL CYLINDER LOCK Many attempts have been madeto obtain bidirectional function in a disc cylinder lock having alockable and releasable lock cylinder which is released by rotating thelocking discs of the lock with a key into a cylinder releasing positionand wherein the discs must be rotated to their initial cylinder lockingposition to allow removal of the key. Due to the special characteristicsof this type of locks, bi-directional function has not been able toobtain unless additional actions have been introduced into the operationcycle of the lock, as for instance an additional axial moment, differentkey insertion positions, etc. Locks with a complicated operation are notsuitable as standard locks in doors or the like. That is why earliersolutions for obtaining bidirectional function in cylinder locks of thiskind referred to must be considered unsatisfactory.

The object of the invention is to provide a lock of the kind referredto, with bi-directional function and with the same simple mode ofoperation as in normal unidirectional disc cylinder locks. By providingthe lock with a reset member and a slip clutch two operating directionscan be obtained without deviating from the simple operation cycle knownfrom uni-directional locks of basically the same kind.

The words slip clutch", whenever used in this specification and in theclaims, mean a clutch providing a slipping action when a certain torqueload is exceeded but functioning otherwise as a fixed coupling member.

The reset member may be located in the keyway of the lock, or at theperiphery of the locking discs, or between the keyway and the peripheryof the locking discs, in a free space provided for this purpose. Thefirst mentioned embodiment provides good guidance of the locking discs.The reset member also prevents access to the interior of the lockmechanism and thus gives extra protection against picking attempts. Thesecond embodiment makes it possible to reduce the outer diameter of thelock, but it also makes it difficult to obtain proper guidance of thelocking discs. The third embodiment allows the most compact design to beachieved. On the other hand it weakens the locking discs, which may haveto be made open so that the space provided for the reset member extandsall the way from the keyway opening to the periphery of the lockingdiscs.

The slip clutch is most suitably located at one end of the lock,preferably at the outer end of the lock, so that the torque needed tofree the clutch is transmitted from the strongest part ofthe key blade,that is the part close to the key bow. The slip clutch can be providedwith balls, protrusions or corresponding parts, which in certainpositions are pressed by a spring member into matching recesses in theopposite clutch member. The clutch may work in axial or in radialdirection or in any intermediate direction. A radial clutch has theadvantage, that the spring member can be of annular configuration and sothat it does not transmit any reaction forces to other parts of the lockmechanism. The clutch may be designed to have no particular couplingpositions, or there may be a great number of coupling positions close toeach other. However, three coupling positions are quite sufficient, twoof which correspond to the end positions of the turning movement of thekey relatively to the turnable cylinder of the lock, and onecorresponding to the insertion and removal positionof the key. A clutchwith only a few coupling positions is naturally easier to manufactureand is also more reliable in service.

In a lock mechanism according to the invention, the locking discs arepreferably, in a way known per se, provided with a radial inwardlyextending protrusion in the control opening that receives the key. Thisprotrusion is influenced by the combination surface of the key providedat the position of each single disc. The combination surfaces for eachof the two operating directions engage opposite sides of saidprotrusion.

In locks according to the invention, the reset member may transmitnot-desired turning movements to the locking discs through frictionalcontact with them. In order to avoid this the lock can be provided in away known per se, with intermediate discs between the locking discs,non-rotatably fixed to the movable cylinder. By giving the intermediatediscs somewhat greater radial dimensions than the locking discs in adirection towards the reset member, undesired contact between the resetmember and the locking discs is avoided.

The invention will now be described by way of example, with reference tothe accompanying drawings showing schematically different embodiments ofthe invention. In the drawings,

FIG. 1 is a cross-sectional view of a lock according to a firstembodiment of the invention,

FIG. 2 is an axial section view of the lock of FIG. 1,

FIG. 3 is a cross-sectional view of a key of the lock,

FIG. 4 is an axial section view of a lock according to a secondembodiment of the invention,

FIG. 5 shows section V-V of FIG. 4,

FIG. 6 shows section VIVI of FIG. 4 and FIG. 7 is a cross-sectional viewof a lock according to a third embodiment of the invention.

In the drawings, 1 indicates the turnable cylinder of the lock and 2locking discs enclosed within the cylinder. The cylinder land thelocking discs 2 are enclosed within the immovable .cylinder housing 3.When the key of the lock is not inserted, the cylinder 1 is nonrotatablyfixed to the cylinder housing 3 by means of a locking bar 4 partiallylocated in an axial groove 5 in the cylinder housing 3 and partially inan axial slot 6 in the cylinder 1. The locking of the cylinder is notreleased merely by insertion of the key 7 into the keyway 8 of the lockmechanism. Only when the key after insertion is turned to the right orthe left through a certain angle, the cylinder 1 is released as therecesses 9 in the locking discs 2 are brought in a position, in linewith the locking bar 4. The recesses 9 form in this position a groovewhich receives the locking bar 4, when a torque is transmitted to thecylinder 1 by turning the key further in the same direction. After thisoperation the cylinder 1 can be freely rotated in the initially chosenturning direction of the key.

Most of the locking discs 2 are rotatable between a zero-position, shownin FIG. 1, in which the insertion and removal of the key of the lock ispossible, and two other positions, called releasing positions, in whicheither one of the recesses 9 of the locking discs lined-up at theposition of the locking bar 4. The location of the recesses 9 in thelocking discs determines the combination value of each locking disc,that is the angle the disc has to be turned from its zero-position toits releasing position. As later on will be explained, the key of thelock is provided for each locking disc with two combination surfaces,each of them acting in its own turning direction. When the key isturned, its different combination surfaces rotates each of the lockingdiscs through the right angle (in the embodiment shown, 18, 36, 54, 72or 90) so that all the locking discs are brought into releasing positionallowing the cylinder to be rotated. One or some of the locking discshaving a turning angle of 0 may be non-rotatably fixed to the innercylinder 1. These so called fixed locking discs are used to transmit thetorque from the key 7 to the cylinder 1. A fixed locking disc (and any 0turning disc) has only one recess 9, which is constantly in releasingposition, that is, at the position of the locking bar 4. The fixedlocking discs are non-rotatably secured to the inner cylinder 1 by meansof a protrusion 10 which is received by an axial groove 11 in thecylinder 1. This groove receives also corresponding protrusions of amember of intermediate discs, located between the locking discs 2 tokeep the locking discs out of direct contact with each other. Theintermediate discs, are also non-rotatably fixed to the cylinder 1.

In the embodiment shown in FIG. 1, the reset member of the lock islocated in the keyway 8 of the lock. When turned, the key engagestheradial inward protrusions 13 in the central opening of the lockingdiscs. In order to allow removal of the key from the lock mechanism,every locking disc must be brought back to the zero-position. This isobtained by transmitting torque from the key through a clutch to thereset member 12, the radial contact surfaces 24 and ofwhich engages,each in its own rotation direction, the protrusions 13 of the lockingdiscs, thus bringing the locking discs back to their zero position, whenthe key is turned back to its zero position.

FIG. 1 shows the position of the parts of the lock mechanism after alock operation including releasing of the locking action by turning thekey 7 counter clockwise and relocking by turning the key back into Zeroposition. If after such an operation the opposite operation direction ofthe lock is to be used, the slip clutch, which will be described indetail below, occupies another coupling position. This is because thekey 7 and the reset member 12, coupled together by the clutch so thatthe reset member seeks to follow the clockwise turning movement of thekey but is prevented from doing so by the protrusions 13 of the fixedlocking discs, which as already explained are non rotatably fixed to thecylinder 1. As the reset member 12 cannot be rotated clockwise, theclutch between the key and the reset member slips and occupies a newcoupling po- I sition upon turning the key clockwise through its fullturning angle relatively to the cylinder 1. This rotation of the keybrings simultaneously the locking discs to their releasing position.When the key is turned back, the radial face 24 of the reset member, nowrecoupled to the key, engages the protrusion 13 of each of the rotatedlocking disc and brings them back to the zero position. A repeatedopening of the lock in clockwise direction does not cause any slip inclutch between the key and the reset member, but a change back tocounter clockwise operation causes the clutch to slip back into theposition illustrated in FIG. 1.

FIG. 2 shows in principle the sectional view II-II of FIG. 1, yet withthe exception of the key 7 which is not shown in FIG. 2. FIG. 2 is alsomore schematical than FIG. 1 in that the clearances between the parts ofthe lock mechanism are not shown.

FIG. 2 shows how the slip clutch 15 is arranged at the outer end of thecylinder housing 3. The clutch 15 connects the key of the lock and thereset member 12. The clutch slipswhen a certain torque is exceeded, butfunctions otherwise as a fixed coupling. The torque is transmittedthrough the clutch by a number of balls 17, which in certain positionsare urged by a clutch spring 16 into corresponding recesses 18 in theclutch part of the reset member 12. The function of the lock requiresonly a few fixed clutch positions, while the clutch otherwise can beslipping. If the clutch comprises four balls 17 and correspondingrecesses 18 arranged with a regular pitch on the clutch faces, therewill be four fixed clutch positions at right angles to each other. Oneof these clutch positions should then correspond to the zero position ofthe key of the lock and two other positions should correspond to themaximum turning angle of the key relatively to the cylinder 1. Theclutch part 15 is provided with a protrusion, connecting this partnon-rotatably to the key when the key is in the lock mechanism. Thisprotrusion is not shown in FIG. 2 because it is located outside thesectional view plane.

FIG. 3 is a schematical cross-sectional view of a keytype, which can beused in a lock according to the invention. The key bow is indicated by19 and the key blade by 7 in FIG. 1. The contour line 20 is theunmachined profile of the key blade. By cutting straight across the keyblade at number of combination surfaces 21a, 21b, 21c, 21d, 21c and21fcan be produced. These combination surfaces act on the locking discs2 when the key is turned counter clockwise as seen from the key bow(clockwise according to FIG. 3). The corresponding combination surfaces22a, 22b, 22c, 22d, 22a and 22f on the other side of the key act on thelocking discs 2, as the key is turned clockwise, seen from the directionof the key bow (counter clockwise according to FIG. 3).

FIG. 3 shows only one of many possible key profiles and key cuttingpatterns. The key can be modified in several different ways. Essentialis only that the key has a number of combination surfaces which when thekey is turned rotate the different locking discs to their releasingposition. As the lock has two operating directions, also the key musthave two sets of combination surfaces, one for each operating direction.

FIG. 4 shows a second embodiment of the invention. The clutch acts inthis embodiment in radial direction and comprises as in the embodimentshown in FIG. 2, clutch balls 17 and a clutch spring 16. The clutchspring 16 is annular which gives the advantage that no reaction forcesare transmitted to the cylinder housing 3 or to the cylinder 1. Thereset member 12 is located on the periphery of the locking discs 2.

FIG. 5 shows the clutch 15 with its balls 17 and spring 16, and thecoupling recesses 18 in the reset member 12 as seen in a sectionperpendicular to the longitudinal axis of the cylinder housing.

FIG. 6 shows that the turnable cylinder 1 in this embodiment of theinvention, has'been reduced to two narrow axial wings each on its ownside of the locking bar 4. This is necessary in order to providesufficient space at the periphery of the locking discs 2 for the twoaxial wings of the reset member 12 and the protrusions 10 locking theintermediate discs 14 and the fixed locking discs of the lock relativelyto the cylinder 1. The

locking discs 2 are provided with a protrusion 23 to which the resetmember 12 transmits torque when the locking discs are to be returnedinto zero position. In order to avoid undesired contact between thereset member 12 and the locking discs 2, the intermediate discs 14 aresomewhat larger in the radial direction than the locking discs 2 withinthe sectors where the reset member moves. The same method has been usedin the embodiment shown in FIGS. 1 and 2 where the intermediate discs 14have a somewhat smaller central opening than the locking discs 2.

In the embodiment shown in FIG. 7, the reset member 12 is locatedbetween the keyway 8 of the lock and the periphery of the locking discs2. In order to simplify the manufacturing of the parts of the lock, thelocking discs 2 have been made open, that is, their central opening hasno limit in the sector where the reset member 12 moves. The fixedlocking discs and the intermediate discs are non-rotatably fixed to thecylinder 1 by means of protrusion 10, Two such protrusions are shown,but in principle one is sufficient. The lock of FIG. 7 functions in thesame manner as the locks illustrated by FIGS. 1 to 2 and 4 to 6,respectively. The clutch of the lock of FIG. 7 can be of the axial typeas in FIG. 2 or of the radial type as in FIG. 4.

The invention is not limited to the embodiments shown, but severalvariations and modifications are feasible within the scope of thefollowing claims.

I claim:

1. A cylinder lock mechanism comprising a cylinder housing with acylindrical opening, a cylinder turnable in said opening and providingat its turning axis a free space for a plurality of locking discsprovided with a central opening forming the keyway of the lock mechanismand being turnable by means of a key of the lock mechanism relative tosaid cylinder both in clockwise and in counter clockwise direction froma key insertion position into a cylinder-releasing position, said lockmechanism including a turnable reset member, connected through a slipclutch to said key of the lock when the key is in operating position insaid keyway, so that turning of said key from its cylinder-releasingposition back to its insertion position, causes a corresponding turningmovement of said reset member which is provided with contact surfacesengaging said locking disc and returning them during said movement totheir initial position allowing removal of said key from said lockmechanism.

2. A lock mechanism according to claim 1, in which said reset member islocated in said keyway of the lock mechanism.

3. A lock mechanism according to claim 1, in which said reset member islocated at the periphery of said locking discs.

4. A lock mechanism according to claim 1, in which said reset memberoperates in an opening provided in said locking discs between saidkeyway of the lock mechanism and the periphery of said locking discs.

5. A lock mechanism according to claim 1, in which said clutch islocated at an end portion of said lock cylinder.

6. A lock mechanism according to claim 1, in which said clutch comprisesa first part having a number of recesses and a second part havingprotruding members fitting into said recesses, and a spring memberarranged to press said parts of the clutch towards each other.

7. A lock mechanism according to claim 1, in which said clutch hasseveral coupling positions, two of which correspond the extremepositions of said key relative to said cylinder and one corresponds tosaid insertion position of said key.

8. A lock mechanism according to claim 1, in which each locking disc, inthe keyway of the lock mechanism, has a radially inwards extendingprotrusion having contact surfaces to be engaged by correspondingcombination surfaces on said key for turning said discs intocylinder-releasing position.

9. A lock mechanism according to claim 1, having intermediate discsbetween said locking discs, which intermediate discs are non-rotatablyfixed relative to said cylinder, the radial dimension of saidintermediate discs in a direction towards said reset member exceedingthe corresponding dimension of said locking discs, thus preventingradial contact between said reset member and said locking discs.

1. A cylinder lock mechanism comprising a cylinder housing with acylindrical opening, a cylinder turnable in said opening and providingat its turning axis a free space for a plurality of locking discsprovided with a central opening forming the keyway of the lock mechanismand being turnable by means of a key of the lock mechanism relative tosaid cylinder both in clockwise and in counter clockwise direction froma key insertion position into a cylinder-releasing position, said lockmechanism including a turnable reset member, connected through a slipclutch to said key of the lock when the key is in operating position insaid keyway, so that turning of said key from its cylinder-releasingposition back to its insertion position, causes a corresponding turningmovement of said reset member which is provided with contact surfacesengaging said locking disc and returning them during said movement totheir initial position allowing removal of said key from said lockmechanism.
 2. A lock mechanism according to claim 1, in which said resetmember is located in said keyway of the lock mechanism.
 3. A lockmechanism according to claim 1, in which said reset member is located atthe periphery of said locking discs.
 4. A lock mechanism according toclaim 1, in which said reset member operates in an opening provided insaid locking discs between said keyway of the lock mechanism and theperiphery of said locking discs.
 5. A lock mechanism according to claim1, in which said clutch is located at an end portion of said lockcylinder.
 6. A lock mechanism according to claim 1, in which said clutchcomprises a first part having a number of recesses and a second parthaving protruding members fitting into said recesses, and a springmember arranged to press said parts of the clutch towards each other. 7.A lock mechanism according to claim 1, in which said clutch has severalcoupling positions, two of which correspond the extreme positions ofsaid key relative to said cylinder and one corresponds to said insertionposition of said key.
 8. A lock mechanism according to claim 1, in whicheach locking disc, in the keyway of the lock mechanism, has a radiallyinwards extending protrusion having contact surfaces to be engaged bycorresponding combination surfaces on said key for turning said discsinto cylinder-releasing position.
 9. A lock mechanism according to claim1, having intermediate discs between said locking discs, whichintermediate discs are non-rotatably fixed relative to said cylinder,the radial dimension of said intermediate discs in a direction towardssaid reset member exceeding the corresponding dimension of said lockingdiscs, thus preventing radial contact between said reset member and saidlocking discs.